Significance Alzheimer's disease is a severe neurodegenerative disorder affecting older populations. In addition to other neurotransmitter systems the cholinergic system is severely affected in this disorder. Nerve Growth Factor (NGF) has been proposed as one treatment for this disorder. Objectives These experiments are determining whether the introduction of NGF to the basal forebrain is a safe, practical and effective means of NGF delivery for the potential therapy of human neurodegenerative disorders such as Alzheimer's disease. Results Adult rhesus monkeys have received intraparenchymal grafts of NGF-secreting cells to the cholinergic basal forebrain. Cell doses have been adjusted by incremental increases in cell volume, holding density and rate of infusion constant. To date, it appears that an optimal cell dose range has been determined. Based upon these findings, potential clinical trials in humans may be undertaken as a means of neuroprotection in Alzheimer's disease. Future Directions Once optimal doses ranges have been confirmed, an application will be submitted for human clinical trials. KEY WORDS aging, Alzheimers, NGF FUNDING NIH Grant AG10435